Famed tech investor Vinod Khosla and his venture firm, Khosla Ventures, announced today the firm had closed a $1.05 billion venture fund, one of the largest new venture funds this year.

The Khosla Ventures IV will make early-stage investments in the areas of clean tech, IT, mobile, and Internet technology, with half the fund going toward clean tech, he said.

"We have identified the 'Clean Dozen' companies in clean tech that can achieve unsubsidized market competitiveness and the 'Cool Dozen' categories in Internet and mobile in the post-PC world such as big data, emotion, interest graphs and consumer health," Khosla said in a statement.

After becoming a partner at Kleiner Perkins Caufield & Byers , Khosla left the investment heavyweight and got into green-tech investing out of environmental concerns. In the past, Khosla's namesake investment firm has raised more than $1 billion to invest in a range of clean-energy technologies, such as LED lighting, solar energy, and battery technology, as well as all manner of infrastructure products, such as low-polluting steel, cement, and glass.

Khosla said at a recent conference that he remains bullish on green-tech investing despite a significant downturn in the amount of money venture capitalists have put into the field this year and the bankruptcy of Solyndra, the government-backed company whose failure has created a political uproar.